The future of the Danube River Basin
Adaptation to environmental change is not a new concept; throughout history societies have shown a strong capacity for adapting to different climates and environmental changes. Nevertheless, human-induced climate change represents a new and rapidly progressing challenge, one that society and the natural environment are not entirely protected against.
A healthy river basin is the foundation for economic, social and cultural development. More than 80 million people living in the Danube region depend on rivers and their ecosystems. Human activities have placed pressure on waters in the Danube Basin: households, industries and agriculture have all contributed to a decrease in water quality, leading to the establishment of the ICPDR to address these issues. Now, Danube countries must come together to better understand and prepare for the effects of climate change.
The Danube Declaration, adopted by the Danube countries at a Ministerial Conference in February 2010, acknowledged that “the impacts of climate change will increase and develop into a significant threat in the Danube River Basin”. Furthermore, through the Declaration the ICPDR was asked to develop a Climate Change Adaption Strategy by 2012 to address these impacts. In addition, climate change adaptation issues must be fully integrated into the second Danube River Basin Management Plan as well as the first Flood Risk Management Plan, both due in 2015.
Getting a picture of future impacts. Germany was nominated as the lead country to steer the process under the framework of the ICPDR, and is supported by a team of experts in this field. To provide a basis for discussions on the strategy, the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety supported a Danube Climate Change Adaptation Study. The study began in December 2010 and was completed in January 2012 by Professor Wolfram Mauser and scientists from the Ludwig-Maximilians-Universitaet in Munich, in continuous exchange with the ICPDR. The results provide the foundation for a common, Danube-wide understanding of waterrelated climate change impacts.
Though no new modelling was done, the study summarises existing information available from more than 90 ongoing and completed research and development projects and studies, as well as 60 adaptation strategies, EU activities and guidance documents, national communications and reports. This information was then analysed for commonalities, contradictions, dependencies, knowledge gaps and competing interests for possible conflicts in order to provide an overview and assessment of state-of-the-art knowledge for the Danube River Basin.
“The study provides a really comprehensive overview of the status quo of what we know at the moment about climate change and climate adaptation in the Danube River Basin,” says Knut Beyer, Co-Chairperson of the ICPDR River Basin Management Expert Group. “It is a sound basis for the ICPDR to elaborate its Adaptation Strategy.”
Preliminary study results were presented during ICPDR meetings and international workshops and conferences to establish contacts with experts in the Danube River Basin and to gather futher information from projects and climate change adaptation activities. In particular, a special roundtable discussion for the Team of Experts was organised in Munich in September 2011 to discuss the initial results and determine further project steps.
clIMaTe chaNge: whaT To exPecT
The Danube Climate Change Adaptation Study presents expected climate change impacts throughout the basin.
Warm and dry regions are expected to experience a higher demand of water for irrigation with the decrease in precipitation in summer. The upper basin might benefit from a longer growing period, but the middle and lower basins might experience a shorter growing season with yield losses.
An increase in air and water temperature might lead to a decrease in biodiversity and changes in ecosystems in the Danube River Basin in the long term. While some native species are expected to disappear, invasive species might increase.
Impacts on hydropower are connected to changes in water availability. Therefore, future hydropower generation is likely to decrease, especially during summer months.
Low water levels, in combination with a reduced flow velocity, are expected to reduced cargo and limit navigability, especially in the middle basin. However, high winter temperatures could result in less frost and icing.
A reduction in water availability, changes to river regimes, drought or flood events and an increase in water temperature could result in water bodies being more vulnerable to pollution and lead to a decrease in water quality.
Expected effects of climate change. According to the study results, air temperature is expected to increase with a gradient from northwest to southeast. From 2021 to 2050, an annual increase of 0.5° C in the upper basin to 4° C in the lower basin is expected. Between 2071and 2100, an increase of 2.5° and 5° C is expected. At the end of the century, the increase is expected to be particularly large during summer for the south-eastern region of the basin.
Precipitation is expected to increase for northern Europe and decrease for southern Europe. For the Danube region in the middle, this means that annual precipitation for the whole region will probably remain constant, but seasonal changes are expected to occur, with a decrease in summer and an increase in winter. For south-eastern Europe in particular a reduction of about 25% to 45% is expected.
Although the study does not reveal a clear picture of the floods, periods of drought, low-flow and water scarcity are likely to become more intense, longer and more frequent. A general increase in water demand due to socio-economic developments is expected for households, industry and agriculture, which could lead to high water stress. All this, together with an increase in water temperature, could further endanger water quality.
From study to strategy. An ICPDR Climate Change Adaptation Workshop will be held in Munich on 29–30 March 2012 to discuss the study results and possible adaptation measures. This will provide important input for the elaboration of a concrete Danube Climate Change Adaptation Strategy in 2012, with a first-draft table of contents to be discussed at the River Basin Management Expert Group meeting in May 2012. The strategy is expected to be adopted by the Heads of Delegation to the ICPDR in December 2012.
Once in place, the Climate Change Adaptation Strategy will define the next steps towards integrating climate adaptation issues in the first Flood Risk Management Plan, as well as the second Danube River Basin Management Plan to be finalised by 2015.
The Climate Change Adaptation Strategy will also be a concrete step toward the implementation of the EU Danube Strategy, which includes a call for action to “anticipate regional and local impacts of climate change through research” in that Strategy’s Priority Area 5 ‘Managing Environmental Risks’.
For more information or to download the Danube Climate Change Adaptation Study, please visit: www.icpdr.org.